The present invention relates generally to a refrigeration system and, more particularly, the present invention relates to a mechanism for sealing a refrigeration deck within the refrigeration system.
In the beverage industry and elsewhere, refrigeration systems are found in vending machines, glass door merchandisers (xe2x80x9cGDM""sxe2x80x9d), and other types of dispensers and coolers. These systems generally have used a conventional vapor compression (Rankine cycle) refrigeration apparatus to chill beverages or other products therein. In the Rankine cycle apparatus, the refrigerant in the vapor phase is compressed in a compressor so as to cause an increase in temperature. The hot, high-pressure refrigerant is then circulated through a heat exchanger, called a condenser, where it is cooled by heat transfer to the surrounding environment. As a result, the refrigerant condenses from a gas back to a liquid. After leaving the condenser, the refrigerant passes through a throttling device where the pressure and the temperature of the refrigerant are reduced. The cold refrigerant leaves the throttling device and enters a second heat exchanger, called an evaporator, located in or near the refrigerated space. Heat transfer with the evaporator and the refrigerated space causes the refrigerant to evaporate or to change state from a saturated mixture of liquid and vapor into a superheated vapor. The vapor then leaves the evaporator and is drawn back into the compressor so as to repeat the cycle.
Although the Rankine cycle systems adequately chill the products therein and are in widespread use, there are several known disadvantages. First, the systems are generally large and heavy. Second, the systems may be noisy to operate. Third, the systems may have a significant power draw. Further, conventional Rankine systems generally use refrigerants for their working medium. These refrigerants are known to be harmful to the environment. The refrigerants may in some cases be noxious. In fact, although the commonly used HFC refrigerant (134a) is generally assumed not to be noxious, there have been claims to the contrary. This refrigerant, however, is known to be a powerful xe2x80x9cgreenhousexe2x80x9d gas.
One alternative to the use of a Rankine cycle system is a Stirling cycle cooler. The Stirling cycle cooler is also a well-known heat transfer mechanism. Briefly described, a Stirling cycle cooler compresses and expands a gas (typically helium) to produce cooling. This gas shuttles back and forth through a regenerator bed to develop much greater temperature differentials than may be produced through the normal Rankine compression and expansion process. Specifically, a Stirling cooler may use a displacer to force the gas back and forth through the regenerator bed and a piston to compress and expand the gas. The regenerator bed may be a porous element with significant thermal inertia. During operation, the regenerator bed develops a temperature gradient. One end of the device thus becomes hot and the other end becomes cold. See David Bergeron, Heat Pump Technology Recommendation for a Terrestrial Battery-Free Solar Refrigerator, September 1998. Patents relating to Stirling coolers include U.S. Pat. Nos. 5,678,409; 5,647,217; 5,638,684; 5,596,875; and 4,922,722, all incorporated herein by reference.
Stirling cooler units are desirable because they are nonpolluting, efficient, and have very few moving parts. The use of Stirling coolers units has been proposed for conventional refrigerators. See U.S. Pat. No. 5,438,848, incorporated herein by reference. The integration of a free-piston Stirling cooler into a conventional refrigerated cabinet, however, requires different manufacturing, installation, and operational techniques than those used for conventional compressor systems. See D. M. Berchowitz et al., Test Results for Stirling Cycle Cooler Domestic Refrigerators, Second International Conference. As a result, the use of the Stirling coolers in, for example, beverage vending machines, GDM""s, and other types of dispensers, coolers, or refrigerators is not well known.
There is a desire, therefore, for adapting Stirling cooler unit technology to conventional beverage vending machines, GDM""s, dispensers, coolers, refrigerators and the like. Specifically, the Stirling cooler units used therein should be easily accessible in the case of repair or replacement while maintaining adequate efficiency. Preferably the Stirling coolers should be accessible with a minimum of down time for the enclosure as a whole and without the need for emptying the enclosure. The beverage vending machine, GDM, or other type of dispenser, cooler, or refrigerator with the Stirling cooling units therein should be both easy to use and energy and thermally efficient.
The present invention thus provides a refrigeration device. The refrigeration device may include a refrigeration deck frame and a refrigeration deck removably positioned within the refrigeration deck frame. The refrigeration deck may include a sealing member and a seal compression mechanism positioned thereon. The seal compression mechanism may include a rotating member so as to urge the sealing member against the refrigeration deck frame.
Specific embodiments of the refrigeration device may include the refrigeration deck having a cold compartment and a hot compartment. The refrigeration deck may include a liquid secondary loop heat exchanger. The refrigeration deck may include a Stirling cycle cooler. The refrigeration deck may include an air aperture. The air aperture may be surrounded by the sealing member. The refrigeration deck may include a return aperture and a supply aperture. The sealing member may include a supply aperture sealing member and a return aperture sealing member. The sealing member may be made out of extruded vinyl, compliant elastomeric foam, or extruded compliant foam.
The refrigeration deck may include a number of flanges. One of the seal compression mechanisms may be positioned on each of the flanges. The seal compression mechanism may include a base. The base may be made out of a material with a low coefficient of friction. The base may include a number of apertures therein. A shaft may be positioned for rotation within the base. The rotating member may be fixedly attached to the shaft. A handle may be connected to the shaft such that rotation of the handle will cause rotation of the rotating member. The rotating member may include a tab, a cam, or an elongated member.
The seal compression mechanism may include a shaft positioned for horizontal motion within the base. The shaft may have one or more pins positioned thereon. The rotating member may include a number of cams positioned within the base such that the cams may ride along the pins of the shaft.
The refrigeration deck frame may include a number of rails such that the refrigeration deck may slide thereon. The rotating member of the seal compression mechanism may rotate against the rails so as to lift the refrigeration deck. The refrigeration deck frame may include a first end and a second end. The rails may be positioned about the first end. The rotating member may urge the sealing member against the refrigeration deck frame with less than one (1) revolution or about ninety (90) degrees of rotation.
A further embodiment of the present invention may provide for a refrigeration deck for use in a refrigeration device. The refrigeration deck may include an outer frame and a refrigeration device positioned within the outer frame. A sealing member and a sealing member compression device may be positioned on the outer frame. The sealing member compression device may include a rotating member. The rotating member may urge the sealing member against the refrigeration device with less than one (1) revolution. The rotating member may include a tab, a cam, or an elongated member. The refrigeration device may be a Stirling cycle cooler.
A further embodiment of the present invention may provide for a refrigeration device. The refrigeration device may include a refrigeration deck frame with a refrigeration deck removably positioned therein. A sealing member may be positioned between the refrigeration deck and the refrigeration deck frame. A seal compression mechanism may be positioned about the refrigeration deck and the refrigeration deck frame. The seal compression mechanism may include a rotating member so as to urge the refrigeration deck and the sealing member against the refrigeration deck frame.
The deck may include a Stirling cycle cooler. The sealing member may include compliant foam, rubber, or vinyl. The sealing member and the seal compression mechanism may be attached to the refrigeration deck or the refrigeration deck frame.
The seal compression mechanism may include a base. The base may include a number of apertures therein. A shaft may be positioned for horizontal motion within the base. The shaft may include one or more pins positioned thereon. The rotating member may include a number of cams positioned within the base such that the cams may ride along the pins of the shaft. The cams may include one or more pairs of ramps with a gap therebetween. The rotating member may urge the sealing member against the refrigeration deck frame with less than one (1) revolution.
The method of the present invention may provide for sealing a refrigeration deck within a refrigeration deck frame. The refrigeration deck may include a sealing member and a sealing member compression device. The refrigeration deck frame may include a number of rails positioned therein. The method may include the steps of sliding the refrigeration deck into the refrigeration deck frame along the rails and rotating the sealing member compression device against the rails so as to lift the refrigeration deck and compress the sealing member against the refrigeration deck frame. The refrigeration deck may include a Stirling cycle cooler. The method further may include the step of operating the Stirling cycle cooler.
These and other features of the present invention will become apparent upon review of the following detailed description of the disclosed embodiments when taken in consideration with the drawings and the appended claims.